CCNA 2 - Capitulo 3

CCNA 2 - Capitulo 3

1. VLAN (VIRTUAL LANs)

   • TYPE VLANs
     • VLAN DEFAULT
       • VLAN 1 (VLAN DEFAULT )
         • VLAN 1 CANNOT BE DELETED OR RENAMED
         • THE MANAGAMENT VLAN IS VLAN 1 BY DEFAULT
         • THE DEFAULT VLAN ON A CISCO SWITCH IS VLAN 1
         • ALL SWITCH PORTS ARE ON VLAN 1
         • THE NATIVE VLAN IS VLAN 1 BY DEFAULT
       • R1#SHOW VLAN BRIEF
     • VLAN DATA
       • USER GENERATED TRAFFIC
       • VLAN VOICE & VLAN MANAGEMENT TRAFFIC ON DATA VLANs
         • NOT BE PERMITTED
         • NOT CARRY
     • VLAN NATIVE
       • CONFIGURE UNSED VLAN
       • NATIVE VLAN ON A CISCO SWITCH IS VLAN 1 (DEFAULT VLAN)
       • TRUNK PORTS BETWEEN SWITCHES
         • UNTAGGED TRAFFIC
           • TRUNK PORT PLACES UNTAGGED TRAFFIC ON THE NATIVE VLAN
         • TAGGED TRAFFIC (802.1Q)
           • TRUNK PORT INSERTs A 4 BYTE TAG IDENTIY VLAN
     • VLAN MANAGEMENT (MGMT)
       • SSH , TELNET , HTTPS , SNMP
       • IS A DATA VLAN
       • BY DEFAULT VLAN 1 IS CONFIGURED AS THE MANAGEMENT
     • VLAN VOICE
       • PORT SWITCH
         • SUPPORT DATA E VOICE
       • VOIP TRAFFIC REQUIRES THE FOLLOWING
         • BROADCAST TRANSMISSION PRIORITY OVE OTHER TYPES OF TRAFFIC
         • ASSURE BANDWIDTH
         • DELAY OF LESS 150MS
         • ABILITY TO BE ROUTED AROUND CONGESTED AREAS
       • VOICE VLAN TAGGING
         • A SEPARETE VOICE VLAN IS REQUERID TO SUPPORT VOIP
           • ENABLE SPLIT
             • QUALITY OF SERVICE (QoS)
             • SECURITY POLICIES
         • HOW IS THE CONNECTION MADE?
           • 1 - CONNECTS TO THE SWITCH A VOIP DEVICE
           • 2 - CONNECTs TO PC A VOIP DEVICE
         • SWITCH ACCESS PORT SENDS CDP PACKETS
           • ATACHED IP PHONE TO SEND TRAFFIC - IN ONE OF THREE WAYS
             • 1 - VOICE VLAN TRAFFIC MUST BE TAGGED
               • LAYER 2 CLASS OF SERVICE (COS) PRIORITY VALUE
             • 2 - ACCESS VLAN TRAFFIC CAN ALSO BE
               • TAGGED WITH A LAYER 2 COS PRIORITY VALUE
             • 3 - ACCESS VLAN IS NOT TAGGED
               • NO LAYER 2 COS PRIORITY VALUE
         • HOW TO VIEW VLAN VOICE ASSIGN TO PORT ?
           • S1# SHOW INTERFACES F0/18 SWITCHPORT
   • VLANS DEFINITIONS
     • VIRTUAL LAN (VLANs)
     • SEGMENTATIONS BASED ON FACTORS SUCH AS
       • FUNCTION
       • TEAM
       • APPLICATIONS
     • LOGICAL CONNECTIONS
     • EACH SWITCH PORT CAN BE ASSIGNED ONLY VLAN PER PORT
       • EXCEPT PORT CONNECTED TO AN IP PHONE OR TO ANOTHER SWITCH
   • BENEFITS OF VLAN DESIGN
     • SEGMENT AND FLEXIBILIZE
     • SECURITY ; EFICIENCY
       • ONLY SAME VLANS CAN COMMUNICATE TOGETHER
     • SIMPLER PROJECT AND MANAGEMENT
     • REDUCED COST
     • ARE CREATED AT LAYER 2
       • REDUCING OR ELIMINATE BROADCAST TRAFFIC
     • VLAN DESIGN MUS TAKE INTO CONSIDERATION
       • HIERARHICHAL ADDRESSING SCHEME
     • BETTER PERFORMANCE
       • REDUCE UNNECESSARY TRAFFIC
     • SMALLER BROADCAST DOMAINS
       • IMPROVE NETWORK PERFORMANCE
         • UNICAST , BROADCAST AND MULTICAST PACKETS
           • FORWARDED AND FLOODED ONLY SAME DOMAIN BROADCAST
       • REDUCES NUMBER OF DEVICES IN THE BROADCAST DOMAIN

2. VLANs IN MULTI SWITCHED ENVIRONMENT

   • VLAN IDENTIFICATION WITH A TAG 802.1Q
     • BY DEFAULT ETHERNET FRAME DOES NOT CONTAIN TAG
     • TAGGED BY USING IEEE 802.1Q HEADER
       • 4 BYTE TAG INSERTED
         • VLAN TAG FIELD DATAILS
           • 2 BYTES (16 bits )
             • (TPID) TYPE
               • HEXADECIMAL 0X8100
               • TAG PROTOCOL ID
           • 2 BYTES (16 bits )
             • USER PRIORITY 1 bit
               • IMPLEMENTATION
                 • SERVICE
                 • LEVEL
             • (CFI) CANONICAL FORMAT IDENTIFIER 1bit
               • ENABLES TOKEN RING TO BE CARRIED ACROSS ETHERNET LINKS
             • (VID) VLAN ID 12 bits
               • SUPPORTS UP TO 4096 VLANS
               • IDENTIFICATION VLAN
       • 1518 BYTES ORIGINAL FRAME
   • NETWORK WITHOUT VLAN
     • FORWARDS ALL PORTS EXPECT WHERE WAS RECEIVED
   • NETWORK WHITH VLANs
     • BROADCAST TRAFFIC ARE RESTRICTED TO THE DEVICES THAT ARE IN THAT VLAN
   • NATIVE VLAN AND 802.1Q TAGGIND
     • UNTAGGED FRAMES NATIVE VLAN
       • PORT RECEIVES UNTAGGED FRAMES
         • IT FORWARDS THOSE NATIVE VLAN
       • NATIVE VLAN SHOULD NOT BE TAGGED
     • TAGGED FRAMES NATIVE VLAN
       • RECEIVES TAGGED FRAME WITH VLAN ID SAME AS NATIVE VLAN ?
         • IT DROPS THE FRAME
     • 802.1Q SPECIFIED A NATIVE VLAN FOR TRUNK LINKS
       • WHEN AN UNTAGGED FRAME ARRIVES ON A TRUNK PORT ? IS ASSIGNED TO THE NATIVE
   • VLANS WOULD NOT BE VERY USEFUL WITHOUT VLAN TRUNKS